CAMP HILL, Pa. — Rite Aid is selling whooping cough vaccines to parents in California at a reduced price, the retailer said Thursday.

As of July 1, a new state law will require proof of vaccination for all students entering grades 7 through 12, and nearly all of the retail pharmacy chain’s 600 stores in California will be able to vaccinate walk-in patients or by appointment. The reduced-price vaccine will sell for $57.99.

“Rite Aid is proud to make it easier — and cheaper — than ever for parents to get their children vaccinated against whooping cough, all well ahead of the start of the fall 2011 school year,” Rite Aid EVP pharmacy Robert Thompson said. “Rite Aid pharmacists stand ready to help meet the demand for convenient access to vital immunizations.”

For proof of vaccination, Rite Aid is participating in the California Immunization Registry, issuing wallet-sized immunization cards and issuing proof of past whooping cough vaccinations at any Rite Aid location.